Aromatic polyimide composition

Abstract

The present invention relates to a new aromatic polyimide composition containing an aromatic polyimide and a polyarylene of a specific type, and to articles and parts of articles made thereof.

1. A blend (B) comprising:
 at least one aromatic polyimide (P1), and 
 at least one polyarylene (P2), more than 50 wt. % of the recurring units thereof are optionally substituted arylene groups [recurring units (R2)], each of said recurring units (R2) being linked by each of its two ends to two other optionally substituted arylene groups via a direct C—C linkage, and said recurring units (R2) being a mix (M) consisting of:
 between 0 and 75 mole %, based on the total number of moles of recurring units (R2), of rigid rod-forming arylene units (R2a), optionally substituted by at least one monovalent substituting group, with 
 between 25 and 100 mole %, based on the total number of moles of recurring units (R2), of kink-forming arylene units (R2b), optionally substituted by at least one monovalent substituting group. 
 
 
     
     
       2. The blend according to  claim 1 , wherein the weight of the polyarylene (P2), based on the combined weight of the aromatic polyimide (P1) and the polyarylene (P2), is of at least 5%. 
     
     
       3. The blend according to  claim 2 , wherein the weight of the polyarylene (P2), based on the combined weight of the aromatic polyimide (P1) and the polyarylene (P2), is of at most 30%. 
     
     
       4. The blend according to  claim 1 , wherein the combined weight of the aromatic polyimide (P1) and the polyarylene (P2), based on the total weight of the blend (B), is above 95%. 
     
     
       5. The blend according to  claim 1 , wherein the recurring units (R2) of the polyarylene (P2) are a mix (M) consisting of:
 between 0 and 75 mole %, based on the total number of moles of recurring units (R2), of rigid rod-forming arylene units (R2a) chosen from p-phenylenes optionally substituted by at least one monovalent substituting group, 
 
       with
 between 25 and 100 mole %, based on the total number of moles of recurring units (R2), of kink-forming arylene units (R2b) chosen from (i) m-phenylenes optionally substituted by at least one monovalent substituting group and (ii) mixes of m-phenylenes with o-phenylenes, wherein both m-phenylenes and o-phenylenes are, independently from each other, optionally substituted by at least one monovalent substituting group. 
 
     
     
       6. The blend according to  claim 5 , wherein the rigid rod-forming arylene units (R2a) of the mix (M) are p-phenylenes substituted by a phenylketone group. 
     
     
       7. The blend according to  claim 5 , wherein the kink-forming arylene units (R2b) of the mix (M) are unsubstituted m-phenylenes. 
     
     
       8. The blend according to  claim 1 , wherein, in the mix (M), the number of moles of the kink-forming arylene units (R2b), based on the total number of moles of the recurring units (R2), is of at least 40%. 
     
     
       9. The blend according to  claim 1 , wherein, in the mix (M), the number of moles of the kink-forming arylene units (R2b), based on the total number of moles of the recurring units (R2), is of at most 65%. 
     
     
       10. The blend according to  claim 1 , wherein the aromatic polyimide (P1) is an aromatic polyetherimide. 
     
     
       11. The blend according to  claim 10 , wherein more than 50 wt. % of the recurring units of the aromatic polyimide (P1) are recurring units (R1) chosen from recurring units (R1c-4) 
       
         
           
           
               
               
           
         
       
       as such, and/or in their amic acid forms 
       
         
           
           
               
               
           
         
       
       wherein:
 the → denotes isomerism so that in any recurring unit the groups to which the arrows point may exist as shown or in an interchanged position; 
 E is chosen from: 
 
       (E-i) 
       
         
           
           
               
               
           
         
       
       with the R′ being, independently from each other, alkyl radicals comprising from 1 to 6 carbon atoms, aryls or halogens; 
       (E-ii) 
       
         
           
           
               
               
           
         
       
       with n=integer from 1 to 6; 
       (E-iii) 
       
         
           
           
               
               
           
         
       
       with the R′ being, independently from each other, alkyl radicals comprising from 1 to 6 carbon atoms, aryls or halogens; 
       (E-iv) 
       
         
           
           
               
               
           
         
       
       with the R′ being, independently from each other, alkyl radicals comprising from 1 to 6 carbon atoms, aryls or halogens;
 and Y being chosen from: 
 (Y-i) alkylenes of 1 to 6 carbon atoms, in particular 
 
       
         
           
           
               
               
           
         
       
       with n=integer from 1 to 6,
 (Y-ii) perfluoroalkylenes of 1 to 6 carbon atoms, in particular 
 
       
         
           
           
               
               
           
         
       
       and 
       
         
           
           
               
               
           
         
         with n=integer from 1 to 6, 
         (Y-iii) cycloalkylenes of 4 to 8 carbon atoms; 
         (Y-iv) alkylidenes of 1 to 6 carbon atoms; 
         (Y-v) cycloalkylidenes of 4 to 8 carbon atoms; 
       
       
         
           
           
               
               
           
         
         Ar″ is selected from: 
       
       (Ar″-i) aromatic hydrocarbon radicals having from 6 to 20 carbon atoms and halogenated substituted thereof, or alkyl substituted derivatives thereof, wherein the alkyl substituting group contains 1 to 6 carbon atoms, such as: 
       
         
           
           
               
               
           
         
       
       and halogenated substituted thereof, or alkyl substituted derivatives thereof, wherein the alkyl substituting group contains from 1 to 6 carbon atoms; 
       (Ar″-ii) 
       
         
           
           
               
               
           
         
       
       with Y being chosen from (Y-i), (Y-ii), (Y-iii), (Y-iv), (Y-v), (Y-vi), (Y-vii), (Y-viii), (Y-ix) and (Y-x), as above defined, 
       (Ar″-iii) alkylene and cycloalkylene radicals having from 2 to 20 carbon atoms, and 
       (Ar″-iv) terminated polydiorganosiloxanes. 
     
     
       12. The blend according to  claim 11 , wherein more than 50 wt. % of the recurring units of the aromatic polyimide (P1) are recurring units (R1) of formula (XXXVIII) as such, in imide form, and/or in amic acid forms [formulae (XXXIX) and (XL)]: 
       
         
           
           
               
               
           
         
         wherein in formulae (XXXIX) and (XL) the → denotes isomerism so that in any recurring unit the groups to which the arrows point may exist as shown or in an interchanged position. 
       
     
     
       13. The blend according to  claim 11 , wherein essentially all the recurring units of the aromatic polyimide (P1) are recurring units (R1). 
     
     
       14. A method for preparing the blend (B) according to  claim 1 , said method comprising melt mixing the at least one aromatic polyimide (P1) with the at least one polyarylene (P2). 
     
     
       15. The method according to  claim 14 , comprising extruding the aromatic polyimide (P1) with the polyarylene (P2), so as to obtain strands of the blend (B). 
     
     
       16. A shaped article or a part of a shaped article comprising the blend according to  claim 1 . 
     
     
       17. The shaped article or the part of a shaped article according to  claim 16 , which is selected from a group consisting of films, fibers, coating, and membranes. 
     
     
       18. A process for preparing the shaped article or the part of a shaped article according to  claim 16 , wherein the blend (B) is injection molded. 
     
     
       19. A method for increasing the fire resistance of an aromatic polyimide (P1) in the need thereof, said method comprising blending said aromatic polyimide (P1) with at least one polyarylene (P2),
 wherein more than 50 wt. % of the recurring units of the polyarylene (P2) are optionally substituted arylene groups [recurring units (R2)], each of said recurring units (R2) being linked by each of its two ends to two other optionally substituted arylene groups via a direct C—C linkage, and said recurring units (R2) being a mix (M) consisting of:
 between 0 and 75 mole %, based on the total number of moles of recurring units (R2), of rigid rod-forming arylene units (R2a), optionally substituted by at least one monovalent substituting group, with 
 between 25 and 100 mole %, based on the total number of moles of recurring units (R2), of kink-forming arylene units (R2b), optionally substituted by at least one monovalent substituting group. 
 
 
     
     
       20. The method according to  claim 19 , which is a method for reducing the heat released and/or the smoke generated during the combustion of the aromatic polyimide (P1) in the need thereof. 
     
     
       21. A method for increasing the impact resistance of an aromatic polyimide (P1) in the need thereof, said method comprising blending said aromatic polyimide (P1) with at least one polyarylene (P2),
 wherein more than 50 wt. % of the recurring units of the polyarylene (P2) are optionally substituted arylene groups [recurring units (R2)], each of said recurring units (R2) being linked by each of its two ends to two other optionally substituted arylene groups via a direct C—C linkage, and said recurring units (R2) being a mix (M) consisting of:
 between 0 and 75 mole %, based on the total number of moles of recurring units (R2), of rigid rod-forming arylene units (R2a), optionally substituted by at least one monovalent substituting group, with 
 between 25 and 100 mole %, based on the total number of moles of recurring units (R2), of kink-forming arylene units (R2b), optionally substituted by at least one monovalent substituting group.